Structure and ultrastructure of the ventral prostate of isogenic mice (C57B1/6J) submitted to chronic alcohol ingestion

Morphological and functional alterations caused by chronic alcohol ingestion in testes and accessory sex organs have been studied both in man and in laboratory animals. The aim of the present study was to examine the possible occurrence of deleterious effects of chronic alcohol ingestion on the secretory epithelium of the ventral prostate of mice. Twenty-four adult male C57BL/6J mice were divided into three groups. The alcohol-treated group was allowed to drink only 6% (v/v) ethanol, the isocaloric group received a diet of water/sucrose with a calorie content equivalent to a 6% alcohol solution and the control group received water. Both groups were fed ad libitum with solid Purina rat chow. After 120 days, animals from each group were anesthetized with ethyl ether, weighed and processed for light and transmission electron microscopy. The results demonstrated reduction in the glandular epithelium cell height and disorganization of the Golgi complex. Moreover, abundant membrane-bound structures, most likely representing cytoplasmic material, were observed, as well as accumulation of dense bodies. Statistical analysis showed that bodyweight gain was similar for both groups. In conclusion, chronic alcohol ingestion has harmful effects on the secretory epithelium cells of the ventral lobe of the prostate of mice after 120 days of treatment. (C) 2001 Harcourt Publishers Ltd.

Toxicity of chronic ethanol ingestion and superoxide radical formation on seminal vesicles of rats

The toxic effects of chronic ethanol ingestion were evaluated in male adult rats for 300 days. The animals were divided into three groups: the controls received only tap water as liquid diet; the chronic ethanol ingestion group received only ethanol solution (30%) in semivoluntary research; and the withdrawal group received the same treatment as chronic ethanol-treated rats until 240 days, after which they reverted to drinking water. Chronic ethanol ingestion induced increased lipoperoxide levels and acid phosphatase activities in seminal vesicles. Cu-Zn superoxide dismutase (SOD) decreased from its basal level 70.8 +/- 3.5 to 50.4 +/- 1.6 U/mg protein at 60 days of chronic ethanol ingestion. As changes in GSH-PX activity were observed in rats after chronic ethanol ingestion, while SOD activities were decreased in these animals, it is assumed that superoxide anion elicits lipoperoxide formation and induces cell damage before being converted to hydrogen peroxide by SOD. Ethanol withdrawal induced increased SOD activity and reduced seminar vesicle damage, indicating that the toxic effects were reversible, since increased SOD activity was adequate to scavenge superoxide radical formation. Superoxide radical is an important intermediate in the toxicity of chronic ethanol ingestion. Copyright (C) 1996 Elsevier B.V. Ltd

DOES SNATCHING FREQUENCY REALLY INDICATE FOOD INGESTION IN THE NILE TILAPIA

The fitness of the snatching frequency as an indicator of food intake in Nile tilapia finger-lings, Oreochromis niloticus (L), was studied. Five groups of four individuals each were used after a two-day starvation period. The hierarchical rank among individuals in the same group was registered. Food in the form of tiny pellets (ranging from 1.30 to 1.95 mm in diameter) was offered, and the individual snatching frequency was observed during a 20-min period. The animals were then sacrificed for evaluation of stomach contents. It was concluded that snatching frequency is not a good parameter to indicate individual food intake in this species when fed as a group with pellets crushed into tiny particles. This raises a problem for investigations that require evaluation of the cumulative effect of competition on food intake, such as growth or conversion efficiency studies. Furthermore, a very low correlation between snatching frequency and food intake was shown in the third hierarchical rank. It is suggested that the linearity assumed in such hierarchies should be reconsidered.

Interaction between the lateral preoptic area and the subfornical organ in the control of water ingestion caused by cellular dehydration, hypotension, hypovolemia, and deprivation

Water intake was studied in albino rats with lesions in the lateral preoptic area, in the subfornical organ, and in both the lateral preoptic area and the subfornical organ. Drinking was induced by cellular dehydration, hypovolemia, hypotension (isoproterenol or caval ligation), and water deprivation. The animals with lesions in both areas showed a significant reduction in their water intake in response to cellular dehydration. Drinking due to extracellular dehydration was reduced in the animals that received only subfornical organ lesions, and was reduced even further in the animals with both areas ablated. The lesions in the subfornical organ were sufficient to reduce the thirst induced by caval ligation. The lesions in both areas inhibit water intake induced by caval ligation. Water intake induced by deprivation was reduced when both areas were destroyed. These findings demonstrate that both the lateral preoptic area and the subfornical organ are necessary for normal drinking in response to cellular dehydration, hypovolemia, and hypotension. There is further evidence that the lateral preoptic area and subfornical organ interact in the control of water intake induced by a variety of thirst challenges.

Ultrastructural study of the coagulating gland of Wistar rats submitted to experimental chronic alcohol ingestion

Morphological changes of coagulating gland of Wistar rats submitted to the experimental chronic alcoholism were noted. Ultrastructurally, it was observed reduction of the granular endoplasmic reticulum cisternae and nuclei with basal position and irregular shape. The epithelial cells presented pycnotic nuclei and the mitochondrial cristae disappeared, characteristic of cellular degeneration.

Ultrastructural study of the lateral lobe of the prostate of Wistar rats submitted to experimental chronic alcohol ingestion

Alcoholism is considered today one of the most serious social and medical problems. Different investigators have demonstrated that chronic exposure to alcohol causes morphological and physiological changes in the testes and in the accessory sex glands, in the prostate in particular. In the present study, experimental rats were divided into groups receiving sugar cane brandy diluted to 30° G.L. (30%, v/v) and Purina ration ad libitum for 60, 120, 180, 240 and 300 days, respectively. At the end of each period the animals were sacrificed and the lateral lobe of the prostate was collected for histological examination. The results showed atrophied epithelium, accumulation of lipidic droplets and rupture of the microvilli that line the cell surface facing the lumen of cells of the secretory epithelium of the lateral lobe of the prostate.

Ultrastructural changes on the epithelial cells of uterine tubes of Wistar rats after chronic ethanol ingestion

The present paper describes the morphological alterations of the epithelial layer of the uterine tubes of rats submitted to experimental chronic alcoholism using anatomical, histological, ultrastructural and morphometric methods. Sixty adult rats (Rattus norvegicus albinus) at the same age (3 months) and with a mean body weight of 228 g were divided into two groups. The control group received solid diet (Purina rat chow) and tap water ad libitum. The alcoholic group received the same solid diet and was allowed to drink only sugar cane brandy dissolved in 30° Gay Lussac (v/v). After periods of 90, 180 and 270 days of treatment animals at normal estrus were anaesthetised with ethyl ether, weighed and sacrificed. Subsequently, the uterine tubes were dissected, weighed and prepared for TEM and SEM methods. The final mean body weights were similar in the control and alcoholic groups. The morphometric analysis showed no difference between control and alcoholic epithelial height. The alcoholic animals showed ultrastructural alterations: intense lipid droplet and lysosomes accumulation, dilated rough endoplasmic reticulum cisternae and vacuolization in both periods of treatment. It was concluded that alcohol acts as a toxin on the epithelial layer of the uterine tubes of rats.

Energetic cost of predation: Aerobic metabolism during prey ingestion by juvenile rattlesnakes, Crotalus durissus

We investigated the cost of prey ingestion in the South American rattlesnake, Crotalus durissus, to see if the capacity to generate energy aerobically could be a constraint on the size of the prey that can be ingested. To accomplish this goal, we measured time and aerobic metabolism (inferred from oxygen consumption) of juvenile C. durissus ingesting prey ranging from 10 to 50% of their own body mass. Time needed for prey ingestion increased with prey size, with prey representing 10 and 20% of snake size being ingested with the same effort. Whole animal rates of oxygen consumption increased linearly with prey size, but at a slower pace for snakes ingesting prey larger than 30% of their body mass. Aerobic factorial power input necessary for prey ingestion increased with prey size, and for snakes ingesting prey representing 50% of their body mass it equaled the aerobic factorial scope for exercise. For the maximum prey size tested, the aerobic derived energy necessary for prey ingestion represented 0.02% of the total energy content of the prey. Within the prey size range we studied, the cost of ingestion did not constitute any constraint on the size of the prey that can be ingested. These constraints are set by morphological (gape size), ecological (predation risk), and, probably, by physiological parameters, as suggested by the tendency of V̇O2 during ingestion to increase at a slower pace at relative larger prey sizes.

Energetic and physiological correlates of prey handling and ingestion in lizards and snakes

In this review, we summarize the energetic and physiological correlates of prey handling and ingestion in lizards and snakes. There were marked differences in the magnitude of aerobic metabolism during prey handling and ingestion between these two groups, although they show a similar pattern of variation as a function of relative prey mass. For lizards, the magnitude of aerobic metabolism during prey handling and ingestion also varied as a function of morphological specializations for a particular habitat, prey type, and behavior. For snakes, interspecific differences in aerobic metabolism during prey handling seem to be correlated with adaptations for prey capture (venom injection vs. constriction). During ingestion by snakes, differences in aerobic metabolism might be due to differences in cranial morphology, although allometric effects might be a potentially confounded effect. Anaerobic metabolism is used for prey handling and ingestion, but its relative contribution to total ATP production seems to be more pronounced in snakes than in lizards. The energetic costs of prey handling and ingestion are trivial for both groups and cannot be used to predict patterns of prey-size selection. For lizards, it seems that morphological and ecological factors set the constraints on prey handling and ingestion. For snakes, besides these two factors, the capacity of the cardio-respiratory system may also be an important factor constraining the capacity for prey handling and ingestion. © 2001 Elsevier B.V.

Ultrastructural and morphometric analysis on the ovary of Wistar rats after chronic ethanol ingestion

In the present study, seventy-two adult rats (Rattus norvegicus albinus) aged three months were used. The animals were divided into two groups (control and alcoholic). The control group received a solid diet (Purina rat chow) and tap water ad libitum. The alcoholic group received the same solid diet and sugar-cane liquid (trade 51, 41° Gay Lussac - GL) diluted 30° GL. At the end or 90, 180 and 270 days of treatment, ten rats of each group were anaesthetized with ethyl ether and sacrificed. The ovaries were collected, fixed, included and submitted to analysis by both light and electron microscopy. The alcoholic group showed increase in the number of corpora lutea at both 180 and 270 days of treatment, atresic follicles at 270 days of treatment, decreased diameter of corpora lutea at 180 and 270 days of treatment, the granulosa layer of the antral follicles at 180 days of treatment, and gradual regression of the theca antral follicles. Furthermore, an increase in diameter and posterior regression of the antral follicle were observed, as well as vacuolation, increased lipid droplets in the granulosa cell at 90 days and in the theca at 180 and 270 days of treatment and gradually in the interstitial cell. The rats showed ovarian alterations after ingestion of alcohol. There was a correlation between exposure time to the drug and the injury observed.

The influence of fluid ingestion on performance of soccer players during a match

The purpose of this study was to verify the effects of a carbohydrate-electrolyte drink on soccer performance. Twenty soccer players volunteered to participate in the study. Players were allocated to two assigned trials according to their positional roles in the team: CHO group (ingesting a 6% carbohydrate-electrolyte solution at regular 15 minutes intervals) and NCHO (ingesting no fluid) during 75 min on-field soccer game. During the trials, body mass loss, heart rate, time spent running, number of sprints and core temperature were measured. There were statistically significant changes (p < 0.05) in body mass loss (CHO: 1.14 ± 0.37 kg vs. NCHO: 1.75 ± 0.47 kg) and number of sprints performed (CHO: 14.70 ± 4.38 vs. NCHO: 10.70 ± 5.80) between groups. The main finding of the present study indicates that supplementation with a carbohydrate-electrolyte drink during a soccer match is beneficial in helping to prevent deterioration in performance. © Journal of Sports Science and Medicine (2004).

Mouthwash ingestion by preschool children

Even though fluoride provides a significant contribution in dental caries prevention, it is known that its random employment may lead to enamel alterations such as dental fluorosis, besides the possibility of severe systemic alterations. The aim of this study was to evaluate the ingestion of mouthwashes administered to preschool children. It was concluded that parents and teachers of young children must be very careful during the accomplishment of educational programs comprising fluoridated mouthwashes, because of the high possibility of ingestion.